1223

This number is a prime.

The smallest prime (emirp) formed from a Pythagorean quadruple (1-2-2-3). It is also a left-truncatable prime. [Loungrides]

The smallest prime formed by concatenating the sequence of the number of divisors of n (i.e., tau(n)). In this case for n = 1, 2, 3, 4. [Post]

The smallest prime that is not a prime divisor of any Carmichael number with exactly three prime divisors. [Vantieghem]

In the penultimate Bible verse (Revelation 22:20), Lord Jesus has an isopsephia value of 1223. [Slattery]

Prime formed from concatenation of the first four terms of the Golomb sequence.

The smallest prime (emirp) obtained by concatenating an integer with the product and sum of its own digits. [Loungrides]

The larger of only two non-titanic primes p, that is the product of a repunit number and all truncations of itself plus two, i.e., 111*11*1+2. Note that the other such prime, 11*1+2, is also emirp. [Loungrides]

Smallest prime formed by concatenating a number with its ordered distinct prime factors. (For 12, they are 2 and 3.) [Sariyar]